<template>
  <div class="header-container">
    <!-- 顶部导航栏 -->
    <nav class="navbar">
      <!-- 左侧：导航按钮 -->
      <div class="nav-left">
        <router-link 
          v-for="nav in navigation" 
          :key="nav.path"
          :to="nav.path" 
          class="nav-btn" 
          active-class="active"
          :title="nav.description"
        >
          <span class="nav-icon">{{ nav.icon }}</span>
          <span class="nav-text">{{ nav.name }}</span>
          <span v-if="nav.path === '/cart'" class="cart-count">({{ cartItemCount }})</span>
        </router-link>
      </div>

      <!-- 右侧：用户登录状态 -->
      <div class="nav-right">
        <!-- 未登录：显示注册/登录按钮 -->
        <div v-if="!isLoggedIn" class="auth-buttons">
          <button class="auth-btn register-btn" @click="goToRegister">
            注册
          </button>
          <button class="auth-btn login-btn" @click="goToLogin">
            登录
          </button>
        </div>

        <!-- 已登录：显示用户邮箱和退出按钮 -->
        <div v-else class="user-info">
          <span class="user-email">{{ userEmail }}</span>
          <el-button 
            type="text" 
            size="small" 
            class="logout-btn"
            @click="handleLogout"
          >
            退出
          </el-button>
        </div>
      </div>
    </nav>

    <!-- 面包屑导航 -->
    <!-- <div class="breadcrumb">
      <router-link 
        v-for="(crumb, index) in breadcrumbs" 
        :key="index"
        :to="getBreadcrumbPath(index)"
        class="breadcrumb-item"
        :class="{ active: index === breadcrumbs.length - 1 }"
      >
        {{ crumb }}
      </router-link>
    </div> -->
  </div>
</template>

<script>
import { readCart } from '../utils/cartManager'
import { mainNavigation, getBreadcrumb } from '../utils/navigation'
import { getGoodsListV2 } from '../api/shoppingCart'

export default {
  name: 'Header',
  data() {
    return {
      user: null,
      cart: [],
      // 服务端购物车数量（统计 productMachineDtoList 的总条数）
      cartServerCount: 0,
      navigation: mainNavigation,
      // 用户邮箱
      userEmail: ''
    }
  },
  computed: {
    // 计算购物车数量
    cartItemCount() {
      // 只使用服务端数量，避免与本地缓存数量不一致
      return Number.isFinite(this.cartServerCount) ? this.cartServerCount : 0
    },
    // 计算面包屑导航
    breadcrumbs() {
      return getBreadcrumb(this.$route.path)
    },
    // 判断是否已登录（检查localStorage中是否有token）
    isLoggedIn() {
      const token = localStorage.getItem('token')
      return !!token // 有token就是已登录，没有就是未登录
    }
  },
  watch: {},
  mounted() {
    this.loadCart()
    // 监听购物车变化
    window.addEventListener('storage', this.handleStorageChange)
    // 首次加载服务端购物车数量
    this.loadServerCartCount()
    // 监听应用内购物车更新事件
    window.addEventListener('cart-updated', this.handleCartUpdated)
    // 加载用户信息（邮箱）
    this.loadUserEmail()
  },
  beforeDestroy() {
    window.removeEventListener('storage', this.handleStorageChange)
    window.removeEventListener('cart-updated', this.handleCartUpdated)
  },
  methods: {
    loadCart() {
      this.cart = readCart()
    },
    /**
     * 加载服务器购物车数量
     * 根据新接口结构：res.rows[].cartMachineInfoDtoList.length 累加
     */
    async loadServerCartCount() {
      try {
        const res = await getGoodsListV2()
        let total = 0
        
        // 新接口结构：res.rows 是店铺数组，每个店铺有 cartMachineInfoDtoList
        if (Array.isArray(res && res.rows)) {
          total = res.rows.reduce((sum, shop) => {
            const machineList = Array.isArray(shop && shop.cartMachineInfoDtoList) 
              ? shop.cartMachineInfoDtoList 
              : []
            return sum + machineList.length
          }, 0)
        } else if (Array.isArray(res && res.data && res.data.rows)) {
          // 兼容：如果数据在 res.data.rows 中
          total = res.data.rows.reduce((sum, shop) => {
            const machineList = Array.isArray(shop && shop.cartMachineInfoDtoList) 
              ? shop.cartMachineInfoDtoList 
              : []
            return sum + machineList.length
          }, 0)
        }

        this.cartServerCount = Number.isFinite(total) ? total : 0
      } catch (e) {
        // 忽略错误，保持当前显示
        console.error('加载购物车数量失败:', e)
      }
    },
    handleStorageChange(event) {
      if (event.key === 'power_leasing_cart_v1') {
        this.loadCart()
        this.loadServerCartCount()
      }
    },
    handleCartUpdated(event) {
      // 支持事件携带数量 { detail: { count } }
      try {
        const next = event && event.detail && Number(event.detail.count)
        if (Number.isFinite(next)) {
          this.cartServerCount = next
          return
        }
      } catch (e) { /* ignore malformed event detail */ }
      // 无显式数量则主动刷新
      this.loadServerCartCount()
    },
    /**
     * 跳转到登录页
     */
    goToLogin() {
      this.$router.push('/login')
    },
    /**
     * 跳转到注册页
     */
    goToRegister() {
      this.$router.push('/register')
    },
    /**
     * 加载用户邮箱
     * 从localStorage读取用户信息，获取邮箱
     */
    loadUserEmail() {
      try {
        // 从localStorage读取用户信息
        const userInfoStr = localStorage.getItem('userInfo')
        if (userInfoStr) {
          const userInfo = JSON.parse(userInfoStr)
          // 获取邮箱，如果没有邮箱就显示用户名
          this.userEmail = userInfo.email || userInfo.username || '用户'
        }
      } catch (e) {
        console.error('读取用户信息失败:', e)
        this.userEmail = ''
      }
    },
    /**
     * 退出登录
     * 清除所有登录信息，跳转到登录页
     */
    handleLogout() {
      // 清除localStorage中的所有登录信息
      localStorage.removeItem('token')
      localStorage.removeItem('userInfo')
      localStorage.removeItem('leasEmail')
      localStorage.removeItem('userId')
      localStorage.removeItem('username')
      
      // 清空购物车
      this.user = null
      this.cart = []
      this.userEmail = ''
      
      // 提示用户
      this.$message.success('退出登录成功')
      
      // 跳转到登录页
      this.$router.push('/login')
    },
    getBreadcrumbPath(index) {
      const paths = ['/productList', '/cart', '/checkout']
      if (index === 0) return '/productList'
      if (index < paths.length) return paths[index - 1]
      return '/productList'
    }
  }
}
</script>

<style scoped>
.header-container {
  width: 100%;
}

/* 导航栏布局：导航按钮在中间，登录状态在右边 */
.navbar {
  display: flex;
  justify-content: center; /* 主内容居中 */
  align-items: center;
  background: #fff;
  border-bottom: 1px solid #eee;
  padding: 16px 32px;
  margin-bottom: 16px;
  position: relative; /* 让右侧元素可以绝对定位 */
}

/* 左侧导航按钮区域（实际在中间显示） */
.nav-left {
  display: flex;
  gap: 24px;
}

/* 右侧用户登录区域（绝对定位到右边） */
.nav-right {
  display: flex;
  align-items: center;
  position: absolute;
  right: 32px; /* 距离右边32px */
}

.nav-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  background: none;
  border: none;
  font-size: 16px;
  color: #2c3e50;
  cursor: pointer;
  padding: 12px 20px;
  border-radius: 8px;
  transition: all 0.3s ease;
  text-decoration: none;
  outline: none;
  position: relative;
}

/* 导航按钮悬停效果 */
.nav-btn:hover {
  background: #f5f7ff;
  color: #667eea;
  transform: translateY(-2px);
}

/* 导航按钮激活状态 - 紫色渐变，跟登录按钮一样 */
.nav-btn.active {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #fff;
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
  transform: translateY(-2px);
}

.nav-icon {
  font-size: 18px;
}

.nav-text {
  font-weight: 600;
}

.cart-count {
  background: #e74c3c;
  color: white;
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: bold;
  min-width: 20px;
  text-align: center;
}

/* 面包屑导航样式 */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 20px;
  background: #f8f9fa;
  border-radius: 8px;
  margin: 0 20px 20px 20px;
  font-size: 14px;
}

.breadcrumb-item {
  color: #666;
  text-decoration: none;
  transition: color 0.3s ease;
}

.breadcrumb-item:hover {
  color: #42b983;
}

.breadcrumb-item.active {
  color: #2c3e50;
  font-weight: 600;
}

.breadcrumb-item:not(:last-child)::after {
  content: '>';
  margin-left: 8px;
  color: #ccc;
}

/* 未登录：注册/登录按钮样式 */
.auth-buttons {
  display: flex;
  gap: 12px;
}

.auth-btn {
  padding: 8px 20px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s ease;
  cursor: pointer;
}

/* 注册按钮 - 白色背景 */
.register-btn {
  color: #667eea;
  border: 1px solid #667eea;
  background: white;
  cursor: pointer;
}

.register-btn:hover {
  background: #f5f7ff;
}

/* 登录按钮 - 紫色背景 */
.login-btn {
  color: white;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border: none;
  cursor: pointer;
}

.login-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

/* 已登录：用户信息样式 */
.user-info {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 8px 16px;
  /* 去掉灰色背景，更简洁 */
}

/* 用户邮箱显示 */
.user-email {
  color: #2c3e50;
  font-size: 14px;
  font-weight: 600;
}

/* 退出按钮样式 */
.logout-btn {
  color: #e74c3c;
  font-size: 14px;
  padding: 4px 12px;
}

.logout-btn:hover {
  color: #c0392b;
  background: #fee;
}

/* 响应式设计 - 手机端适配 */
@media (max-width: 768px) {
  .navbar {
    flex-direction: column;
    gap: 16px;
    padding: 12px 16px;
  }
  
  .nav-left {
    flex-direction: column;
    width: 100%;
    gap: 8px;
  }
  
  .nav-btn {
    width: 100%;
    justify-content: center;
    padding: 16px 20px;
  }
  
  .nav-right {
    width: 100%;
    justify-content: center;
  }
  
  .auth-buttons {
    width: 100%;
  }
  
  .auth-btn {
    flex: 1;
    text-align: center;
  }
  
  .user-info {
    width: 100%;
    justify-content: center;
  }
  
  .breadcrumb {
    margin: 0 12px 16px 12px;
    padding: 8px 16px;
    font-size: 12px;
  }
}
</style>
  